Stabilizing device



April 25, 1939. Q VON DEN STEINEN 2,155,892

STABILIZ'ING DEVICE Filed Jar 1. 11. 19 38 2 Sheets-Sheet l 08 PITCHDIRECTION April 1939. c. VON DEN STEINEN 2,155,392

STABILIZING DEVICE Filed Jan. 11, 1938 2 Sheets-Sheet 2III-[:ICJCIIIIEIUEIEJEJEIICI Patented Apr. 25, 1939 UNITED STATES PATENTOFFICE many, assignor to Askania-Werke A. G., a c' poration of GermanyApplication January 11, 1938, Serial No. 184,492

' In Germany January 8, 1937 I Claims.

smThis invention relates to stabilizing devices for It is an object ofthis invention to provide a device for exerting stabilizing moments on aship 5 about its longitudinal axis for the purpose of effecting ananti-rolling stabilization of the ship.-

It is a further object to provide a device 'capable of simultaneouslypropelling and stabilizing a ship.

According to this invention I provide in a ship, as hereinafter setforth in detail, a' Schneider propeller adjustable in response tolateral inclinations and capable of exertingmoments about thelongitudinal axis of the ship. The Schneider propeller as an element iswell-known in the art and comprises a rotatable support from which aplurality of blades project parallel to the axis of rotation of thesupport, the blades being adjustable relatively thereto. Depending uponthe ad 90 iustment oi the blades relatively to the support the bladesexert a propelling force in any desired direction normal to the axis ofrotation. According to this invention a Schneider propeller is 'em-'ployed normally to propel the ship and to exert stabilizing moments onthe same upon deviations of the ship from its normal position.

Further aims, objects, and advantages of this invention will appear froma consideration of the description which follows with the accompanylngdrawings showing for purely illustrative pur poses an embodiment of thisinvention. It is to be understood, however, thatthe description is notto be taken in a limiting sense, the scope of this invention beingdefined in the appended claims.

Referring to the drawings: Fig. 1 is a plan view, partly in section, ofa Schneider propeller, the propeller blades being shown in a neutralinactive position. Fig. 2 shows the propeller of Fig. 1 adjusted forpropelling action.

Fig. 3 is a diagrammatic illustration of a ship equipped with astabilizing Schneider propeller. Figs. 4 to 6 are diagrams illustratingdifferent adjustments of the propeller.

Fig. .7 is a diagram illustrating apparatus for adjusting the propellerblades.

The construction and operation of the Schneider propeller are well-knownin the art and described for example in my copending application Ser.184,492 filed January ll, 1938. It may therefore sufiice to show and.describe in connection with this invention only the most essen 1elements of .the propeller.

In support It! rotatable about an axis 2 and ll driven by a "suitablesource (not shown) a plurality of propeller blades I! to "5 are mountedwith their shafts I! to 22 extend parallel to the axis of rotation. Thepropeller blades are of a cross section similar to that of the wing ofan air-plane to offer a minimum resistance to the 5 water. To the shaftsI! to 22 webs 23 to 28 are securedhaving crank pins-'29 to 34 to whichconnecting rods 35 to "are connected. The other ends of the connectingrods are pivotally linked to levers 4| to 46, the levers being pivotallycon- 10 nected to a disk 41 at 48 to 53, respectively. The levers 4| to46 are guided in guiding blocks 54 to 59 pivotally connected at 60 to65, respectively, to a. disk 66 secured to or integral with the supportl0. 15

'Assuming that the disk 41 be adjusted to be concentric to the disk 66and the support I6 it follows that the blades will upon rotation of thesupport It travel ,in a circle indicated in a dashdot line Withoutexerting on the water a force, 20 other than the resistance offered tothe curved front of the blades.

Turning now to Fig. 2, the disk 41 is shown in an excentric positionrelatively to the support l0 and the disk 66. Assuming now that thesupport 2| II] is rotated about the axis 2 in the direction of the arrow3, while the center 4 of the disk 41 is maintained fixed, the propellerblades will perform an oscillating movement about their respectiveshafts and a further movement about the 30 axis 2 with their surfacesinclined relatively to the direction of travel. Accordingly forces willbe exerted on the water as will become still clearer from aconsideration of the diagrammatic Figures 4 to 6. .35

In Figs. 4 to 6 the center of the support is indicated at 2, while thecenter of the disk 41 is indicated at 4. The direction of movement ofthe'blades is again indicated by arrows 3. An axis 5-5 may be assumed tobe parallel tothe longitudinal axis of the ship, while an axis 66 isnormal thereto. v 4

A displacement of the center 4 in the direction of the axis 66 willresult in a movement of the 5 blades which is shown in Fig. 4.

Four diiferent positions o1 the blades are indicated at A to D. Thelever mechanism shown in Figs. 1 and 2 will cause an oscillatinginovement of the blades as follows: A blade which is aligned 50 withthedirection of travel at A will be oscillated in clockwise direction tobecome inclined as shown at B reacting on the water. Thereafter thelevers impart a counter-clockwise oscillation to the blade; At C theblade is again aligned with the direction of travel and at D inclined toreact on the water. I

The oscillating movement of the blades together with the rotary movementin the direction 3 results in a reaction of the blades on thesurrounding water indicated by the arrows I. The direction of theresultant force is approximately normal to a line connecting the centers2 and 4.

A different adjustment of the blades is shown in Fig. 5 caused by adisplacement of the center of the disk 46 into a position 4'. Fourdifferent positions of the blades are again indicated at A to D. Itclearly appears from the position of the blades that a force will beexerted on the water in the direction of the arrows 'I' inclined to thedirection of the axis 6-6.

A still different adjustment of the Schneider propeller is shown in Fig.6. In this example the center 4 is displaced in the direction of theaxis 5-5 resulting in a movement of the blades which is again shown infour phases A" to D". The resultant force on the water is indicated bythe arrows 'I" directed parallel with the axis 6-6 and normal to thelongitudinal axis 5-5 of the ship. a

For exerting stabilizing moments on a ship the Schneider propeller ismounted on the body of the ship in such manner that the propeller bladesprotrude from the ships bottom.

In Fig. 3 a Schneider propeller having a'casing 51 with an electricmotor enclosed therein for driving the propeller is mounted without awater-tight compartment '80 of the ship. A spindle 69 and a nut Iforming part of a worm gear II drivenby a motor I2 permits the casing 61to be lowered into the operative position shown in the drawings in whichthe propeller blades protrude below the bottom of the ship. In shallowwater, wherev damage is likely to occur to the propeller blades, thecasing 61 may be raised into the compartment, whereby the blades are protected.

Inasmuch as the blades are arranged below the center of gravity of theship through which also the longitudinal axis -5 is assumed to pass itis easily understood that the propeller blades are capable of exerting areacting moment on the ship about the axis 5-5, when adjusted inresponse to lateral inclinations of the ship.

Assuming, for example,.that the blades be adjusted as shown in Fig. 6 inwhich the propeller acts on the water in the direction normal to theaxis 5-5 it appears that a maximum moment will be exerted on the ship.

when, in turn, the propeller is so adjusted as to act parallel to theaxis .5-5 it appears that it will assist in a propulsion of the ship.The propeller accordingly fulfills a double purpose, first the purposeof stabilizing'the ship and second the purpose of propelling it. Forpropelling the ship the Schneider propeller may be assisted by the usualpropeller indicated at," in Fig. 3, it being understood that thepropeller I3 may also be dispensed with and the propulsion of the shipbe effected exclusively by the Schneider propeller 01. The course of theship is controlled by the usual rudder I4.

The most effective stabilizing action of the Schneider propeller isobtained when the propeller is positioned below the center of gravity ofthe "ship, but vertically spaced relatively thereto. I have found byexperiments that the stabilizin action is not essentiallyjafi'ected whenthe propeller is positioned spaced not more than one quarter of theship's length from the center of gravity in a horizontal direction. Whenthe horizontal distance of the propellerjs. greater than one quarter'ofthe ships length," the course of the ship will be affected by thepropeller and the direction of the ship be changed rather than itsstability.

A suitable form of apparatus for controlling and adjusting the Schneiderpropeller in response to lateral inclinations of the ship is shown inFig. 7. A pendulum .15 is pivoted at I5 for oscillations transversely tothe direction of travel of the ship. The pendulum may be of the shortperiod type assuming the direction of the apparent vertical or of thelong period type assuming the direction of the true vertical, dependingupon whether it is desired to stabilize the ship with respect to theapparent or the true vertical.

The pendulum in the illustrated example is combined with a follow-updevice including a sector shaped follower 11 provided with a toothededge 'I0meshing with a worm l9 rotatable by a reversible motor 80. Themotor is supplied with current from a battery 8i and controlled bycontacts 82 on the pendulum and 83, 04 carried by the follower. Thecontacts 03 and 84 are connectedwith the motor through leads 85 and 86,while a lead 81 connects the battery with the pendulum.

When the pendulum becomes displaced relatively to the follower, one ofthe pair of contacts 02, 83 or 82 84 will be closed causing the motor toturn the worm I9 in such direction that the follower 'II follows themovement of the pendulum. Thus the position of the follower becomes ameasure of the lateral inclinations of the ship.

The movements of the follower are transmitted to actuate a relay, in theillustrated example shown as being an Askania" jet-pipe relay ineludinga jet-pipe 08 pivoted at 89 and supplied with pressure fluid through aconduit 90 which is issued from the jet-pipe into reception orifices 9|and 92 depending upon the relative position of the jet-pipe and theorifices. A double armed lever 93 is pivotally mounted on the jet-pipeat 94, one arm of the lever being connected with the follower IT bymeans of a link 95, the other arm being connected to an angle lever 95pivoted at 91 through a link 98. The angle lever 90 is moved in responseto the movements of the piston of a servo-motor 98, the piston beingconnected with the angle lever through a link I05; The servo-motor issupplied with pressure fluid from the jet-pipe relay 98 through conduitsI00, IN, and I02. A second repeater servo-motor having a cylinder I03and a piston I04 movable therein may be provided between the conduits IIII and I02 for purposes later to be described.

The servo-motor 98, 99 is connected through a link I06 to actuate amovable lever I01 defining the position of the center 4 of the disk 41(Figs. 1 and'2).

The operation of the device so far describedis as follows:

nection I05, 96 90 acting onlthe other end of the differential lever 93.Accordingly the piston of the servo-motor 99. will at all times assume aposition which is a function of the lateral nation of the ship.

In response to the movements of the servomotor 99 the movable member I01will cause an adiustment ofthe blades of the Schneider propeller bydisplacing the axis 4 relatively to the axis 2 as hereinbeforedescribed.The result is a change in direction of the force exerted by thepropeller on the water. The force exerted on the ship by the propellerina direction difle'rent from the direction of the longitudinal axis 5-5will thus produce a moment about the lontudinal axis to counter-act theinclination of the ship and to erect the same.

The device so far described will effectively stabilize a shipe againstlateral inclinations.

Instead of solely changing the direction of the force of the Schneiderpropeller it may alsobe advantageous to vary the magnitude of thepropeller force. This can be achieved in the following manner. A secondservo-motor having a cylinder I08 and a piston I09 movable therein isconnected to the movable member IN. The

incli servo-motor I08, I09 is controlled by and supplied with pressurefluid from a control valve IIO connected to the servo-motor throughconduits III and H2.

trol valve is moved from a diilerential lever II4 to which a restoringconnection H5, H6, H1 is -linked, the other arm of the differentiallever being controlled by a handle 8. A variable transmission device isinserted between the handle H8 and the differential lever. II4 includingin the illustrated example slotted levers H9 and I pivoted at I2I andI22, respectively. A connecting member I 231engages with pins I24 andI25 the slots in-the'levers ll9and I20.. The. connecting member ispivotally connected to a rod I20 guided at I21 and provided with a pinI28 guided in a curved slot I29 of a cam member I30. The cam member isconnected to be moved from the piston I04 and guided at I3I The positionof the servo-motor-IllB, I09 controlling the movable member I0'I effectsan adjustment of the pitch of the Schneider propeller.

It was explained in connection with Figs. 1

and 2 that in the position in which the axes 4 and 2 coincide, the pitchof the propeller blades is zero and the rotating blades will exert noforce on the surrounding water. When the movable member I0! is displacedthrough the servo-motor I08, I09, the pitch of the'propeller bladesdetermining the magnitude of the propeller force is varied. The pitch ofthe propeller blades is normally set by adjusting the handle IIOoperating the control valves H0 and H3. Thegpredetermined pitch of thepropeller set at the handle II 8 is now increased to vary the reactionforce of the propeller on the water for the purpose of erecting the shipas follows.

When the ship is in its normal upright position, the servo-motors 99 andI03 will be in their central position. In thisinstance the member I23 0!the variable transmission device is in its uppermost position in whichthe ratio oi transmission between the handle IIO and the. difl'erentiallever H4 is one to one. When, however, the ship assumes an inclinationand the pistons of the servo-motors 99 and I03 become displaced, the pinI28 will travel in the curved slot I29 of the cam member I30 in adownward direction, increasing the ratio of transmission between thecontrol handle H8 and the pitch controlling valve H0. The pitch of thepropeller blades and accordingly the force of the propeller is thus Thepiston I I3 of the contorque is exerted on the ship.

increased resulting in an increased erecting moment on the ship.

Obviously, the present invention is not restricted to the particularembodiment herein shown and described. Other forms of inclinationresponsive devices may be used and other forms of control devices foradjusting the blades of the Schneider propeller be employed. Moreover,it is not indispensable that allthe features of this invention be usedconjointly, since they may advantageously be employed in variouscombinations and subcombinations.

Thus, for example, the stabilizing device may be simplified byeliminating the elements of the device for changing the pitch of thepropeller in response to inclinations of the ship. In this instance therepeater servo-motor I03, I04 may be omitted and the conduits IOI, I02be connected at I32.

' being mounted on said body substantially below the center of gravityof the ship; power means for driving said propeller; and meansresponsive to lateral inclinations of the ship and connected to adjustsaid blades, whereby upon a lateral inclination the direction of thepropelling force exerted by the propeller is varied and an erectingtorque is exerted on the ship.

2. The combination with a ships body of apropeller having apluialityofblades and a rotatable support for said blades on which said bladesare adjustably mounted parallel with the axis of rotation of saidsupport, said propeller being mounted on said body to protrude from thebottom thereof and at a horizontal distance from the ships center ofgravity of less than one quarter of the ships length; power means fordriving said propeller; and means responsive to lateral inclinations ofthe ship and connected to adjust said blades, whereby upon a lateralinclination the direction of the propelling force exerted by thepropeller is varied and an erecting The combination with a ships body ofa propeller having a plurality of blades a rotatable support for saidblades on which said blades are adjustably mounted parallel with theaxis of rotation of said support; means for mounting.

said propeller on said body to be projectible and retractable relativelyto the bottom thereof and at a horizontal distance from the ships centerof gravity offlessthan one quarter of the ship's length; power means fordriving said propeller; and means responsive to lateral inclinations oi!the ship and connected to adjust said blades, whereby upon a lateralinclination the direction of the propelling force exerted by thepropeller is varied and an erecting torque is exerted on I the, ship.

' including a servo-motor for adjusting said blades to vary thedirection oftheir propelling action; means for mounting said propelleron said body The pitch controlling handle IIO will now control directlythe control valves I I0 and 4 to protrude from the bottom thereof and atr horizontal distance from the ships center of gravity of less than onequarter of the ships length;

power means fordriving said propeller; andmeans responsive to lateralinclinations of the ship and connected to control said servo-motor,whereby upon a lateral inclination the direction of the propelling forceexerted by the propeller is varied and an erecting torque is exerted onthe ship.

5 The combination with a ship's body 01 a propeller having a pluralityof blades and a rotatable support for said blades on which said bladesare adjustably mounted parallel with-the axis of rotation of saidsupport, said propeller including a first servo-motor for adjusting saidblades to vary the direction of their propelling action and a secondservo-motor for adjusting the pitch of the blades; means for mountingsaid

